Legacy code in enterprise applications can run for long hours or sometimes for days. Because these programs can run for a long time, it is not possible to run multiple scenarios to compare results and pick the best one. One solution may be to run simulations using background mode that require an overnight job. To further exacerbate the problem, in some cases, the data or status may have already been changed while the analysis or calculation is still not finished, which may bring inaccuracy and ineffectiveness.
Another solution may be to let the simulation job run for several hours to eventually find out that the result may not be a satisfying one and further adjustment may be needed. However, since the result has already been saved by the enterprise application, changes to the simulation cannot be made. The only way is to backtrack and perform an operation, such as a de-allocation, that could restore the system and data but cannot restore the time that has already been spent.
Not all enterprise applications have simulation mode. But even if simulation mode is supported, users may need to run the process again to save the results. Users may not often use this functionality, because with simulation mode, the results will not be saved no matter whether the results are negative or positive. In this case, in order to save a job result and apply it to the enterprise application, users need to run the same process twice.
Another drawback of using enterprise applications to run simultaneous simulations it that it is nearly impossible to compare two different results at the same time. For instance, even if a simulation job does not consume too much time, users may wish to run two or more different scenarios at the same time. However, it is not possible to collect the results of different scenarios into one screen for comparison using the enterprise application. As such, it is inconvenient for users to decide which scenario is best or which scenario best fits an enterprise's strategy.